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<tr><th colspan="5" align="center" valign="bottom">PostgreSQL 8.2.3 中文文档</th></tr>
<tr><td width="10%" align="left" valign="top"><a href="typeconv-union-case.html" accesskey="P">后退</a></td><td width="10%" align="left" valign="top"><a href="typeconv.html">快退</a></td><td width="60%" align="center" valign="bottom"></td><td width="10%" align="right" valign="top"><a href="mvcc.html">快进</a></td><td width="10%" align="right" valign="top"><a href="indexes-intro.html" accesskey="N">前进</a></td></tr>
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<div class="CHAPTER"><h1><a name="INDEXES"></a>章11. 索引</h1>
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<dt><b>目录</b></dt>
<dt>11.1. <a href="indexes-intro.html">介绍</a></dt>
<dt>11.2. <a href="indexes-types.html">索引类型</a></dt>
<dt>11.3. <a href="indexes-multicolumn.html">多字段索引</a></dt>
<dt>11.4. <a href="indexes-bitmap-scans.html">组合多个索引</a></dt>
<dt>11.5. <a href="indexes-unique.html">唯一索引</a></dt>
<dt>11.6. <a href="indexes-expressional.html">表达式上的索引</a></dt>
<dt>11.7. <a href="indexes-partial.html">部分索引</a></dt>
<dt>11.8. <a href="indexes-opclass.html">操作符类</a></dt>
<dt>11.9. <a href="indexes-examine.html">检查索引的使用</a></dt>
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<p>索引是提高数据库性能的常用方法。索引可以令数据库服务器以比没有索引快得多的速度查找和检索特定的行。不过索引也在总体上增加了数据库系统的负荷，因此我们应该恰当地使用它们。</p>
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<tr><td width="33%" align="left" valign="top"><a href="typeconv-union-case.html" accesskey="P">后退</a></td><td width="34%" align="center" valign="top"><a href="index.html" accesskey="H">首页</a></td><td width="33%" align="right" valign="top"><a href="indexes-intro.html" accesskey="N">前进</a></td></tr>
<tr><td width="33%" align="left" valign="top"><tt class="LITERAL">UNION</tt>, <tt class="LITERAL">CASE</tt> 和相关构造</td><td width="34%" align="center" valign="top"><a href="sql.html" accesskey="U">上一级</a></td><td width="33%" align="right" valign="top">介绍</td></tr>
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